Cured coatings for automotive applications such as primers and topcoats must have a number of desirable properties. First of all, they should contain low amounts of organic solvent for environmental reasons and should contain a high solids content so that a maximum amount of resin and pigment is transferred to the substrate surface. Cure response should be complete at a relatively low temperature and physical properties of the resultant coating such as adhesion, solvent resistance and appearance should meet automotive standards. Attaining all of these characteristics is difficult and often certain properties have to be compromised so that other properties can be upgraded to meet automotive standards.
The present invention provides for an aqueous binder comprising a blend of resins that provide a particularly desirable blend of properties for automotive applications. The binders, when formulated with color-imparting pigments for color applications, are of relatively high solids content, cure at low temperatures and provide for good physical properties such as adhesion, solvent resistance and appearance.